19672 research outputs found
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Detection of seismograph signal using fiber bundle sensor
No full textThe improvement of an external fiber optic sensor both in design and in operational was conducted based on displacement measurement. The purpose of the investigation is to measure the frequency and the amplitude of seismograph signal using the fiber-optic displacement sensor. This sensor setup consists of an optical fiber transmitter, an optical fiber bundle probe, photodiode detector and a seismograph stimulator. The use of stimulator is as a volcano signal model for the testing process. The sensor has the capability to measure the seismograph signal from 0.5 to 1.5 Hz and the linearity is more than 99 %. The proposed sensor is simple, sensitive, provides high dynamic range, and offers lower cost of the fabrication and thus it is suitable to be applied in real field. Furthermore, this sensor generates more excellent result in accuracy and reliability. © 2020 Elsevier Gmb
Signal enhancement of FBG-based cantilever accelerometer by resonance suppression using magnetic damper
No full textIn this work, we propose the use of a magnetic damper in the FBG-based cantilever accelerometer (FCA) to reduce the distortion of signal due to the infinite signal amplification at the resonant frequency. The magnetic damper comprises a permanent magnet and a U-shape aluminum structure. The permanent magnet serves as a load and is attached to one end of the cantilever whereas the aluminum structure serves as a damper to suppress the cantilever resonance. In the experiment, it is found that the distortion on the detected signal by FCA is reduced when the damper is incorporated, and the detected signal has a higher cross-correlation coefficient (CCC) with a reference signal from a standard capacitive based accelerometer. The introduction of a magnetic damper enables the vibration detection of the FCA in the resonant frequency region with reduced signal distortion and it widens the detection range of the FCA. © 2020 Elsevier B.V
Feasibility of an interprofessional collaborative osteoporosis screening programme in Malaysia
No full textBackground Population screening for osteoporosis using bone mineral density scan is not feasible in Malaysia as this test is costly. Hence, there is a need to develop a more efficient method to screen for osteoporosis.Objectives To determine the feasibility of an interprofessional collaborative osteoporosis screening programme (IPC-OSP). Methods Postmenopausal women aged ≥ 50 years, who had not been diagnosed with osteoporosis were recruited from a primary care clinic from June to August 2014. Patients were assessed for their osteoporosis risk and were counselled on prevention methods. Patients at risk were referred to the doctor with a recommendation for a bone mineral density (BMD) scan. Results Fifty out of 55 patients were recruited (response rate = 90.9%). A total 26/50 (52.0%) went for a bone mineral density scan, none were osteoporotic, 17/50 (34%) were osteopenic, 2/50 (4.0%), were started on osteoporosis medications and 14/50 (28%) modified their lifestyle to improve bone health or started on calcium supplements. Osteoporosis knowledge significantly increased from baseline to month two (46.3 ± 21.4 vs. 79.1 ± 14.3, p < 0.001). Patients had a satisfaction score of 89.8 ± 12.4. Follow-up rates were 83.9% and 100% at months 1 (BMD appointment) and 2 (phone follow up), respectively. The intervention was successfully coordinated. Data entry was determined to be viable based on the researchers’ experience. Conclusion The interprofessional collaborative osteoporosis screening programme was found to be feasible in Malaysia. © 2020, Springer Nature Switzerland AG
Ethnic differences in lifetime cumulative incidence of syncope: the Malaysian elders longitudinal research (MELoR) study
No full textPurpose: To determine the lifetime cumulative incidence of syncope, potential ethnic differences and factors associated with syncope using the Malaysian elders longitudinal research (MELoR) study first wave dataset. Methods: The MELoR study recruited community-dwelling adults aged 55 years and over, selected through stratified random sampling from three parliamentary constituencies. The baseline data collected during the first wave was obtained through face-to-face interviews in participants’ homes using computer-assisted questionnaires. During their baseline assessments, participants were asked whether they had ever experienced a blackout in their lifetime and if they had experienced a blackout in the preceding 12 months. Results: Information on blackouts and ethnicity were available for 1530 participants. The weight-adjusted lifetime cumulative incidence of syncope for the overall population aged 55 years and above was 27.7%. The estimated lifetime cumulative incidence according to ethnic groups was 34.6% for Malays, 27.8% for Indians and 23.7% for Chinese. The estimated 12-month incidence of syncope was 6.1% overall, equating to 11.7% for Malays, 8.7 % for Indians and 2.3% for Chinese. Both Malay [odds ratio (OR) 1.46; 95% confidence interval (CI) 1.10–1.95 and OR 3.62, 95% CI 1.96–6.68] and Indian (OR 1.34; 95% CI 1.01–1.80 and OR 3.31, 1.78–6.15) ethnicities were independently associated with lifetime and 12-month cumulative incidence of syncope, respectively, together with falls, dizziness and myocardial infarction. Conclusion: Ethnic differences exist for lifetime cumulative incidence of syncope in community-dwelling individuals aged 55 years and over in an urban area in Southeast Asia. Future studies should now seek to determine potential genetic, cultural and lifestyle differences which may predispose to syncope. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
From Evidence to Policy: Economic Evaluations of Healthcare in Malaysia - A Systematic Review
No full textObjective
To identify and describe the various economic evaluation studies in Malaysia and to determine the range of incremental cost-effectiveness ratios (ICERs) as reported in these studies.
Methods
A comprehensive search of the scientific electronic databases was conducted (Medline, EBM Reviews, Embase, and hand search) to identify all published economic evaluation studies related to Malaysian healthcare. Two researchers assessed the quality of selected studies using the Critical Appraisal Skills Programme (CASP) checklist and Quality of Health Economic Studies instrument. The assessment was also reviewed by expert members of the Technical Advisory Committee of Health Technology Economic Evaluations (TACHTEE).
Results
A total of 64 full-text articles were assessed for eligibility and included in this systematic review. Thirty studies were partial economic evaluations; the full economic evaluations included 17 cost-effectiveness analyses and 17 cost-utility analyses. From all the reported ICERs, the majority (68%) were categorized as highly cost-effective (ICER of less than 1 gross domestic product (GDP) per capita per quality-adjusted life-years or disability-adjusted life-years gained).
Conclusion
This review identifies information gaps and loopholes in health economics research in Malaysia. Additionally, this study provides the information that the majority of published interventions in Malaysia fell within the cost-effectiveness threshold of 1 GDP per capita per quality-adjusted life-years or disability-adjusted life-years gained
Using SERS-based microfluidic paper-based device (μPAD) for calibration-free quantitative measurement of AMI cardiac biomarkers
No full textRecently, surface enhanced Raman scattering (SERS) has attracted much attention in medical diagnosis applications owing to better detection sensitivity and lower limit of detection (LOD) than colorimetric detection. In this paper, a novel calibration-free SERS−based μPAD with multi-reaction zones for simultaneous quantitative detection of multiple cardiac biomarkers — GPBB, CK−MB and cTnT for early diagnosis and prognosis of acute myocardial infarction (AMI) are presented. Three distinct Raman probes were synthesised, subsequently conjugated with respective detecting antibodies and used as SERS nanotags for cardiac biomarker detection. Using a conventional calibration curve, quantitative simultaneous measurement of multiple cardiac biomarkers on SERS-based μPAD was performed based on the characteristic Raman spectral features of each reporter used in different nanotags. However, a calibration free point-of-care testing device is required for fast screening to rule-in and rule-out AMI patients. Partial least squares predictive models were developed and incorporated into the immunosensing system, to accurately quantify the three unknown cardiac biomarkers levels in serum based on the previously obtained Raman spectral data. This method allows absolute quantitative measurement when conventional calibration curve fails to provide accurate estimation of cardiac biomarkers, especially at low and high concentration ranges. Under an optimised condition, the LOD of our SERS-based μPAD was identified at 8, 10, and 1 pg mL−1, for GPBB, CK−MB and cTnT, respectively, which is well below the clinical cutoff values. Therefore, this proof-of-concept technique shows significant potential for highly sensitive quantitative detection of multiplex cardiac biomarkers in human serum to expedite medical decisions for enhanced patient care. © 2019 Elsevier B.V
Mechanical, antibacterial, and biocompatibility mechanism of PVD grown silver–tantalum-oxide-based nanostructured thin film on stainless steel 316L for surgical applications
No full textSurgical site infection associated with surgical instruments has always been a factor in delaying post-operative recovery of patients. The evolution in surface modification of surgical instruments can be a potential choice to overcome the nosocomial infection mainly caused by bacterial populations such as Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. A study was, therefore, conducted characterising the morphology, hydrophobicity, adhesion strength, phase, Nano-hardness, surface chemistry, antimicrobial and biocompatibility of SS 316L steel deposited with a Nano-composite layer of Silver (Ag) and Tantalum oxide (Ta2O5) using physical vapour deposition magnetron sputtering. The adhesion strength of Ag/AgTa2O5 coating on SS 316L and treated at 250–850 °C of thermal treatment was evaluated using micro-scratch. The Ag/Ag–Ta2O5-400 °C was shown a 154% improvement in adhesion strength on SS 316L when compared with as-sputtered layer or Ag/Ag–Ta2O5-250, 550, 700 and 850 °C. The FESEM, XPS, and XRD indicated the segregation of Ag on the surface of SS 316L after the crystallization. Wettability and Nano-indentation tests demonstrated an increase in hydrophobicity (77.3 ± 0.3°) and Nano-hardness (1.12 ± 0.43 GPa) when compared with as-sputtered layer, after the 400 °C of thermal treatment. The antibacterial performance on Ag/Ag–Ta2O5-400 °C indicated a significant zone of inhibition to Staphylococcus aureus (A-axis: 16.33 ± 0.58 mm; B-axis: 25.67 ± 0.58 mm, p < 0.01) and Escherichia coli (A-axis: 16.33 ± 1.15 mm; B-axis: 26.00 ± 0.00 mm, p < 0.01) when compared with SS 316L or Ag/Ag–Ta2O5-700 °C, which showed no inhibition. The biocompatibility tests on Ag/Ag–Ta2O5-400 °C demonstrated an excellent in cell attachment, F-actin protein expression and proliferation/viability of bone marrow derived mesenchymal stromal on day 14 when compared with uncoated or Ag/Ag–Ta2O5-700 °C. This study shows that the Ag segregation process, hydrophobicity, adhesion strength, crystallization, and hardness progressively improved after the annealing up to 400 °C. © 2019 Elsevier B.V
Fe3O4 nanofluid injected photonic crystal fiber for magnetic field sensing applications
No full textThis work proposes a novel magnetic field sensor based on nanoparticle ferrosoferric oxide (Fe3O4) magnetic fluid for different magnetic field strength from 100 Oe to 160 Oe. Investigations are performed to verify the simulation model and measure the spectral shift for applied magnetic field strength. The results of this task indicate that it has high sensitivity response with the variation of various magnetic field strength (Oe). The reported sensitivity as 83268.46 nm/RIU and 83188.25 nm/RIU for both for X and Y polarization respectively and it will be the maximum sensitivity to the best of knowledge. The other significant of this work that the proposed sensor seem to be as simple structure, low cost, high accuracy and also helpful for microfluidics technology. © 2019 Elsevier B.V
Development of lightweight aggregate mortar skin layer for an innovative sandwich concrete composite
No full textThis research strives to develop a high-temperature resistant lightweight aggregate (LWA) mortar skin layer for use in sandwich concrete composite. The first phase of the research was focused on the development of the LWA mortar while the subsequent phase of work dealt with assessing the performance of the resulting sandwich concrete composite. In phase 1 of the investigation, it was found that mortar incorporating calcium aluminate cement (CAC) as binder and lightweight expanded clay aggregate (LECA) as fine aggregate had the best resistance towards high temperature of 1000 °C. The developed mortar along with basalt fibre mesh were used to form textile reinforced concrete (TRC) as skin layer which could still exhibit residual strength upon heated to high temperature. Furthermore, sandwich composite beam made of the TRC skin and aerated concrete as core had better flexural strength/weight ratio compared to that using conventional EPS foam as the core material. There was also no significant damage found on the sandwich concrete composite upon exposure to direct flame. The findings suggest that the development of the sandwich concrete composite is promising and further works can be explored to improve the performance. © 2019 Elsevier Lt
Positioning of periodic AlN/GaN multilayers: Effect on crystalline quality of a-plane GaN
No full textWe report the effect of 40 pairs of periodic AlN/GaN multilayers on the a-plane undoped-gallium nitride (ud-GaN) grown on r-plane flat sapphire substrate via metal-organic chemical vapor deposition. The influence of the position of the periodic AlN/GaN multilayers was seen to enhance the crystalline quality and surface morphology of the a-plane ud-GaN. The surface morphology analysis via atomic force microscopy has shown that the surface roughness was as low as 1.01 nm upon the insertion of the 40 pairs of periodic AlN/GaN multilayers with an optimum position. The on- and off-axis x-ray ω-scan rocking curves illustrate the enhancement in crystalline quality with a reduction of the full width at half maximum from 0.34° to 0.25° along [0001] direction and 0.91°–0.47° along [1–100] direction. The grown a-plane GaN with periodic AlN/GaN multilayers was seen to exhibit different relaxation strain states at different position as seen from the Raman spectroscopy. Room-temperature photoluminescence spectra shows that the sample with optimum periodic AlN/GaN multilayers position exhibits the lowest yellow and blue luminescence band. © 201